Tx Matrix Plus Dc Power Electrical Safety Guidelines And Warnings; Tx Matrix Plus Dc Power Electrical Safety Guidelines - Juniper TX MATRIX PLUS Hardware Manual

TX Matrix Plus DC Power Electrical Safety Guidelines and Warnings

TX Matrix Plus DC Power Electrical Safety Guidelines

Copyright © 2010, Juniper Networks, Inc.
TX Matrix Plus DC Power Electrical Safety Guidelines on page 421
DC Power Electrical Safety Warnings for M Series, MX Series, and T Series
Routers on page 422
When working with DC-powered equipment, observe the following guidelines:
The following electrical safety guidelines apply to a DC-powered router:
A DC-powered router is equipped with a DC terminal block that is rated for the power
requirements of a maximally configured router. To supply sufficient power, terminate
the DC input wiring on a facility DC source capable of supplying at least 48 A –48 VDC.
We recommend that the 48 VDC facility DC source be equipped with a circuit breaker
rated at 125% of the power provisioned for the input minimum, or as required by local
code. Incorporate an easily accessible disconnect device into the facility wiring. In the
United States and Canada, the –48 VDC facility should be equipped with a circuit
breaker rated a minimum of 125% of the power provisioned for the input in accordance
with the National Electrical Code in the US and the Canadian Electrical Code in Canada.
Be sure to connect the ground wire or conduit to a solid office (earth) ground. A closed
loop ring is recommended for terminating the ground conductor at the ground stud.
Run two wires from the circuit breaker box to a source of 48 VDC. Use appropriate
gauge wire to handle up to 60 A @ –48 VDC, or as required by local code.
A DC-powered TX Matrix Plus router that is equipped with a DC terminal block is
intended only for installation in a restricted access location. In the United States, a
restricted access area is one in accordance with Articles 110-16, 110-17, and 110-18 of
the National Electrical Code ANSI/NFPA 70.
NOTE: Primary overcurrent protection is provided by the building circuit
breaker. This breaker should protect against excess currents, short circuits,
and earth faults in accordance with NEC ANSI/NFPA70.
Ensure that the polarity of the DC input wiring is correct. Under certain conditions,
connections with reversed polarity might trip the primary circuit breaker or damage
the equipment.
For personal safety, connect the green and yellow wire to safety (earth) ground at both
the TX Matrix Plus router and the supply side of the DC wiring.
The marked input voltage of –48 VDC for a DC-powered TX Matrix Plus router is the
nominal voltage associated with the battery circuit, and any higher voltages are only
to be associated with float voltages for the charging function.
Because the TX Matrix Plus router is a positive ground system, you must connect the
positive lead to the terminal labeled
, and the earth ground to the chassis grounding points.
–48V
Appendix A: TX Matrix Plus Safety and Regulatory Compliance Information
, the negative lead to the terminal labeled
RTN
421